Further, I cannot do an IMC or night rating with my restricted medical so have nothing to aim towards (beyond 'experience') to make me a better pilot.
Lots of options for a 'humble' PPL rather than just 'experience' or hours.
Actively hunt out interesting aeroplanes and get some experience in them. Get a tailwheel endorsement. Get aerobatic training. Do formation training etc.
As others have suggested, try gliding. Try the weird and wonderful. Get some hours in micro/ultralights. Hone stick and rudder skills on a fun tail dragger like a Citabria or Cub. You could log a few hundred hours on a Citabria and still feel you could fly it better with a bit more practice. Which is the hook - if it was easy to get polished, you wouldn't enjoy it. That elusive mastery that is always just a little out of your reach is what keeps you addicted.
Lots of things to keep working towards. It is more than just hours. If you really love flying you will never be satisfied with your skills but will want to keep getting just that bit better and more polished. Even if it is a C150, you would be surprised how much you can find to improve.
All this in my opinion but do not discard the satisfaction that can come from flying things other than the big buses and from wearing a casual shirt and jeans rather than a tie and epaulettes.
I think there is a huge difference sitting in a real cockpit in a real aeroplane actually flying, compared to sitting in a simulator and it doesn't have to be a complicated aeroplane either.
A polished performance in a Piper Cub puttering along at 50 knots will easily put a bigger smile on my face than a 737 simulator (and will keep you flying longer). In my opinion anyway.